1. Field of the Invention
The invention relates to a ground apparatus, and more particularly to the ground apparatus applied to solar cell modules that can be both simply structured and easily assembled.
2. Description of the Prior Art
Grounding for solar photovoltaic modules is necessary for assuring the safety to people and the working environment. In the solar photovoltaic system, the solar photovoltaic module is the main element for transforming the solar energy into electric energy. For the solar photovoltaic module would continue to provide a high voltage, in the case that the solar photovoltaic module needs maintenance or replacement, the labor would expose himself/herself in a danger of electric hazard, or the system might be power out due to the damage of the inverter. For most of the solar photovoltaic modules are outdoor units and won't stop their own power generation, the danger of electric hazard is never away. In particular, when a single solar photovoltaic module is connected in series to a photovoltaic array, the maintenance worker would face a risk of electric hazard that would discharge an accumulative voltage from all the connected modules. In addition, no matter what the solar photovoltaic system is a commercial unit or a domestic unit, the system is usually mounted to the roof or a place near the peak of the building. If neighboring constructions are all lower than the building mounting the solar photovoltaic system, the solar panels of the system would be the highest metals in the surrounding area, and inevitably become the easy targets for thunder bombarding. At this time, the ground system provides the least protection against the aforesaid dangers. Further, for the service life of the solar photovoltaic system usually exceeds 40 or 50 years, it is necessary to take into consideration the problem of how to keep a long-term reliable ground system.
Currently, in the safety specs for the solar photovoltaic system, the UL requirements ask the product to have at least minimum mechanical and conductive properties between side frames. In NEC of the US, it is further asked to ground all the conductive surfaces. Namely, each side frame of the solar photovoltaic module shall be grounded. Nowadays, side frames for the solar photovoltaic module are mostly made of aluminum. In order to the endurance, appearance and safety, the side frames are usually prepared by surface polishing, coating and anodizing.
Referring now to FIG. 8, the ground apparatus 200 of the conventional solar cell module is formed by packing the solar panels 220 and the bottom portions of the respective frames 230 located at four corners of the corresponding solar panel. While a worker performs the mounting or installing of a solar energy system in accordance with the aforesaid specs, the solar cell modules are placed on top of a supportive frame 300. Between two solar cell modules, a -shape fastener member 250 is introduced to fix four specific positions at two opposing ends of the vertical frame 230 by respective ground fixation members having individual nuts, washers and screw bolts 240. The conventional ground structure 210 located at a bottom surface 211 of the conjunction of neighboring frames 230 is fixed to the system by a screw bolt 212, an external washer 213, a ground line 214, a flat washer 215, a star-shape washer 216 and a nut 217. Also, the aforesaid conventional ground structure 210 exists in each single solar cell module.
Nevertheless, for the typical solar power system includes a plurality of solar cell modules, while in grounding the system, individual ground line shall be installed to the bottom surface of the frame in each solar cell module. However, for a worker to execute the grounding construction, the working space under the system is extremely limited and narrow. Also, further for the ground line of the solar cell module might need to be extended through a long distance to a perfect ground location, the efficiency and the convenience for the aforesaid grounding setup is extremely low.